Linearity of Tone Controls in the Les Paul Circuit
The following Tone control measurements were taken from recent production Historic Les Paul reissues from the
Gibson Historic Shop. In both cases the functionality of the tone control is most noticeable between settings
of 2 and 3.
Images copyright 2004 Bob Predaina. All Rights Reserved.
Regardless of whether the guitar is outfitted with Linear Taper pots (as in the case of the 1956 LP Reissue)
or Logarithmic Taper pots (in the case of the 1958 LP Reissue), the functionality of the pots is most noticeable
once the control is rolled down to a level of 2 to 3 (in the resistance range of 400k and above).
In these examples, both the P-90 equipped R6 and the Burstbucker equipped R8 displayed markedly "compacted"
response of the tone controls, with the majority of the control's effect being noticed between positions 2 and 3,
regardless of the taper of the potentiometer.
These observations support the opinion among many vintage LP experts who believe that the best sounding LPs
were outfitted with pots having values of about 550k (toward the high end of the manufacturer's tolerance limits).
If your LP is outfitted with Linear Taper pots you will probably notice a slight improvement by changing over
to Audio/Log Taper pots. In some instances, selection of pots with resistance values at the upper limits of the
manufacturer's tolerances may be helpful. The addition of a series resistance may also be helpful to shift the
functionality of the pot into a more "musical" range, although this may cause of a bit of reduction in the guitar's
treble response.
Other methods to consider would include: changing to a higher resistance pot, changing the value of the caps, or
using additional resistors to modify the taper of the pot as discussed in RG Keen's article "The Secret Life of Pots,"
which is available at www.geofex.com.
Last Updated on 5/27/2004
By Bob Predaina
custom_basses AT yahoo DOT com